Many applications and services are personalized based upon the application or service utilizing a user's personal data in order to provide enhanced experiences. When a user gets to a point where he has to make a decision whether to share a particular item of personal data with a certain application or service, such as sharing location data or browsing history upon installation or launch of an application, the user needs to decide whether or not he trusts the application and whether sharing his personal data with the application is worthwhile. If the application is from a well-known, respectful vendor, this decision is easier for the user to make. However, sometimes a user has no way of knowing whether a particular application or service is trustworthy and will not attempt to mis-use his personal data, or whether the application or service gives enough value in return for his data.
Application reputation mechanisms exist that may help the user make this type of decision. However, these mechanisms are limited in that they typically contain a ranking based on how appealing the application or service is to users—and not whether the application is from a trustworthy source, whether the application or application vendor mis-uses personal data or leaks it, or whether the application gives enough value in return for sharing data with it. Moreover, such ranking typically gives all those providing a ranking the same weight, without taking into account the credibility or the thought leadership of the ranker in a certain domain. Moreover, if a user has given consent in the past to an application or service to use his personal data, and the application turns out to be malicious or performing data abuse or privacy violations, the user has no way of knowing that and revoking access to his data for this bad application or service.